Author: Gabriele Gorla

RC2018/04 – 4MB geoRAM Development – Part 2

April 25, 2018 4 Comments on RC2018/04 – 4MB geoRAM Development – Part 2
Posted in Commodore 128, Commodore 64, Featured Article, Hardware, RC2018/04, Retro Challenge

Last weekend we finished the PCB layout and sent it out for manufacturing. The PCB is 83x58mm and fits into a standard Commodore cartridge case. All the ICs are through holes except the DRAM chips. If everything goes well I will receive the boards sometimes next week, just in time for a final blog entry. PLD Code As mentioned in…

RC2018/04 – 4MB geoRAM Development – Part 1

April 13, 2018 2 Comments on RC2018/04 – 4MB geoRAM Development – Part 1
Posted in Commodore 128, Commodore 64, Featured Article, Hardware, RC2018/04, Retro Challenge

RC 2017/10 was my first retrochallenge. I reverse engineered the Berkely Softworks georam for Commodore 64/128 computers, published the design files and built a clone. For RC2018/04 I’d like to pick up where I left off and design a 4MB version of the ram expansion. The Berkeley Softworks geroam is a 512K memory expansion for the Commodore 64/128 originally designed…